Calculating-machine.



' L. D. ROBERTS.

CALCULATING MACHINE.

APPLICATION FILED APR. 9, 190g.

Patented Apr, 6, 1909.

3 SHEETS-SHEET 1.

L. D. ROBERTS.- GALGULATIN G MACHINE. APPLIOATION FILED 11.9.1908.

Patented Apr. 6, 1909.

3 SHEETS-SHEET 2.

L. D. ROBERTS. CALCULATING MACHINE. 'APPLIGATIOH I'ILY'EDIIAPB. 9, 190a.

Patented Apr. 6, 1909.

3 SHEETS-SHEET 3.

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UNITED STATES PATENT ()FFICE.

LORENZO D. ROBERTS, OF SHAWANO, WISCONSIN.

CALCULATING-MACHINE.

I '0 all whom it may concern:

Be it known that I, LORENZO D. RoBnn'rs, residing in Shawano, in thecounty of Shawano and State of WVisconsin, have invented new and usefulImprovements in Calculating-Machines, of which the following is adescription, reference being had to the accompanying drawings, which area part of this specification.

The present invention has to do wit-h that class of calculating machinesdesigned for the use of town, county, or city clerks, or more especiallyfor all persons who have the computing of percentages for a considerableof numbers at a predetermined rate per cent.

This calculating machine is simple in operation, exact in computations,not liable to get out of order, and may be readily used by persons notskilled in mathematical calculations. its parts are based upon the wellknown principles of Arabic notation.

Referring to the accompanying drawings, in which like characters ofreference indicate the same parts in the different views; Figure l is aplan view of a calculating machine constructed in accordance with thisinvention, in its starting or normal condition, that is with no slidedrawn out; Fig. 2 is a similar view thereof with certain slides drawn topositions exemplifying the operation of the device in use and with thebraces removed; Fig. 3 is a similar view of the calculator with the endof the frame swung open to permit of the slides and guides being removedtherefrom, one slide and its shown in a position for removal; Fig. 4t alongitudinal sectional view of the machine on the plane of line -f-l ofFig. 2, with the braces in place; Fig.

is a transverse sectional view of the machine on the plane of line ofFig. 1; Fig. 6 is a detail view of the end of one of the slides, showingthe method of attaching the paper tablet thereto; Fig. 7 is aperspective view of the stay bar; and, Fig. 8 is a longitudinalsectional view of an end of one of the slides, showing a modified formof construction for attaching the tablet.

In these drawings, 10 represents a base or frame consisting of arectangular shallow box, preferably one inch or less in depth, openatthe front or face thereof and having a hinged end 11 at the rightcarrying a stay bar 12 which is provided with guide pins 13 fitting incorresponding openings in guide being Specification of Letters Patent.

Application filed April 9, 1908.

Patented April 6, 1909.

Serial No. 426,037.

the end 11 and which is adjusted in its position by means of set screwsl l threaded in the end 11 and bearing thereon. The adjustability of thestay bar 12 is to enable it to bear against the ends of a series ofnarrow strips forming guides 15, which bear at their other ends againstthe left end of the frame and which alternate with a series of shorterstrips forming slides 16, the stay bar thus preventing the longitudinalmovement of the guides 15 while the slides 16 are free to be movedbetween the guides from their normal. position, as shown in Fig. l, tothe stay bar. To afford a ready means for moving the slides, each isprovided with a loop or knob'2l at its right hand end.

In order that the slides may be firmly held in any position to whichthey may be moved the entire series of slides and guides is subjected topressure by means of a friction bar 17 near the upper edge of the frame,which is loosely mounted on screw posts 18 in said upper edge of theframe and is forced to bear against the series of slides and guides withpressure by means of compression springs 19 surrounding the screw posts18 and adjusted in their compression by set nuts 20 threaded on thescrew posts. By adjusting the nuts 20 on the screw posts 18 the degreeof pressure exerted by the friction bar upon the series of slides andguides may be regulated to permit the slides to be readily moved fromone position to another at will, though preventing their accidentalmoven'ient which would interfere with the operation of the machine.

At the left hand end of each slide it is somewhat modified, as shown inFig. 6, to enable it to carry a tablet 22 consisting of a slip of paperor other suitable material affording a surface on which numbers may bewritten. In that form of the device shown in Fig. 6, the lower corner ofthe slide is recessed and contains a spur 23 on which the strip of paperis impaled after its end has been inserted in an oblique slot 24 leadingfrom the recess, the paper then being carried around the end of theslide and placed flat upon the top surface thereof which for a shortdistance is reduced in height to form a depressed seat for the tablet.At the shoulder formed by this reducti on of the slide is mounted aswinging hook 25 let into the top of the slide and swinging down to ahorizontal position with its pointed end passing through the end of thetablet and into the slide, thus securely and tightly fastening thetablet in place. In the modification of this feature of the invention,as shown in Fig. 8, a swinging hook 26 corresponding to the hook is letinto the reduced end of the slide 16 to engage one end of the tablet 22which is placed in a slot 27 in the end of the slide, the tablet beingdrawn over the end of the slide to cover the hook 26 and engaged at itsother end by the hook 25 as in the former con struction.

As shown in Fig. 2, each slide in addition to the number contained onits removable paper tablet is provided with a permanent number at aboutmidway its length, consisting of a certain digit followed by a series ofzeros, said permanent numbers occupying a space on the slides equal tothe space occupied by the numbers on the tablets and. in the normalposition of the slides being entirely hidden from View by a broad brace28 extending from one side of the frame to the other. Another brace 29is similarly mounted in a posit-ion to cover the column of last digitsin the numbers on the tablets of the slides when the slides are in theirnormal positions, and a third brace 30 is also similarly mounted just inadvance of the loops or knobs 21 when the slides are in their normalposition.

The spaces between the brace 23 and the braces 29 and 30 respectivelyare marked off by parallel cords 31 which are regularly spaced apart thedistance between the digits of the numbers of the slides, such cordsbeing stretched across the base from side to side thereof in anydesirable manner and serving to rule vertical columns upon the numbersof the slides when said numbers are brought therebeneat-h. Forconvenience of description the columns formed between the brace 28 andthe brace 29 are designated by the numeral 32, while the columns formedbetween the braces 28 and 30 are designated by the numeral 33. At thetop of each of these series of columns is a card having the decimalnotation forms marked thereon, as shown in the drawings, and indicatingthe decimal value of the numbers appearing in the columnstherebeneath.The line forming the demarcation between the hundreds and cents is shownin the drawings to be of a difierent color from the others to aid theeye in reading the figures, and in practice a similar change in color ofother lines is used to further assist in this object.

To permit of the slides or the guides being removed for any purpose, asfor renewing the tablets 22 on the former, the hinged end 11 is swungopen, as shown in Fig. 3, permitting the desired members to be drawn outas indicated, and to lock the hinged end in its closed position duringthe operation of the machine hooks 3a are provided on the sides of thebase which engage projections on the hinged end. Directly above eachslide the brace 30 is marked with a number indicating the number of theslide, these numbers being consecutive from 1 to 9 in the low *r slides,while the three extra slides above them are marked 1, 1 and 2respectively. The guides between the slides are correspondinglynumbered. These num here also correspond with the permanent numbers onthe slides, as shown in Fig. 2, that is to say the first digit of thepermanent number on each slide is the same as the number of that slideas shown by the number on the brace 30 directly in front of it and onthe guide directly above it.

In marking the tablets 22, the tablets of slides l, l and 1 are markedwith a munber indicating the given rate per cent. forming the basis ofthe calculations to be made, it being presumed that the decimal pointprecedes the first digit, so that as shown in drawing this rate percent. is 62%6712328 and the tablet of each of the other slides is markedwith a number which a multiple of this rate per cent. corresponding tothe number of the slide, that is to say slides 2 and 2 have a numbershowing twice the rate per cent. and slide 3 has a number showing threetimes the rate per cent. and so forth. These tablet numbers ha ring beenprovided, and care being taken that the digits thereof shall beregularly spaced apart with the same spacing as between the cords ofcolumns 32 and 33, the numbering being preferably made while the tabletis beneath the cords of columns 32 for this purpose, the digit of thepermanent number on the slide 1 eing in the left-hand column of seriesof columns 33, whereupon the machine is in condition to be operated forcalculating the given percentage of any number.

The space to the left of the columns 32 is indicated by the referencecharacter and the space between the columns 32 and 33 is indicated bythe reference character 36, while the space to the right of columns isindicated by the reference character 37. it will be noted that thespaces 32, 3G and 33 are equal, being composed of ten like units ofspace; and this relation of equality remains should any change be madein the number of like unit spaces; that is, were series of columns and33 to be made 9 columns by taking away the left hand column of each,then one unit of like space must be taken from the right hand of bothspaces 35 and 36, the decimal point line (the division between units andtenths or dollars and cents) in series of columns 32 and 33 must be soplaced that the left hand column of series of columns 32 shall be oneorder lower than the left hand column of series of columns 33; andfurther, so the right hand column of series of columns shall representone order lower than the right hand column in series of columns 33, asshown further by decided notation at the heads of these columns.

On the tablets of space 35, any rate per cent. up to one hundred percent. may be written; but if one hundred per cent. or more needs to bewritten a calculator lengthened the required number of like units ofspace would be needed, the lengthening being at the left beyond thespace That is, the relation 01? spaces 35, 32, 30 and 33 must not bechanged.

The space 37, at the right of series of columns 33 and extending to thestay bar 12, carried by the hinged end 11 ot the calculator, must besuch that there is room .for the guard 30, and for the right hand endsof the slides to move a sufficient distance to bring the initial digitof the permanent number into the lowest order of series of columns 33,as shown by the third slide from the top in Fig. 2, \VlEEl'G the numeral2 is shown in the right hand column or series of columns 33. It will beseen that the tenths place on the tablet of this slide is in the lowestorder or in the right hand column of series of columns in which seriespercentages are shown.

Referring to F 2 it will be seen that the calculations are performed bydrawing the required slides to the right until they form in the seriesof columns 33 the number of which the percentage is to be taken at therate per cent. for which the machine is set. he rate per cent. for whichthe machine is set as shown in the drawings is indicated by the secondslide from the top in Fig. 2 to be 0246712328 and begins in the tenthscolumn of series of columns 32 and. extends to the rigl'it into space onthe tablet of the same slide; and its base, 1.00 or $1 on the same slideis in units column of series of columns 33. It will also be seen thatthe first or top slide has the same digit figure 1 for its permanentnumber but that the 1 is in the ten million column of series of columnsand that orders to rightare filled in with zeros, and' the tablet ofthis top slide, though it has the same figures and in the same order asthe tablet on the second slide lies in or under series of columns 32 insuch a position that the zero or tenths place of the rate per cent. isnow in millions order of series of columns 32 and the Fig. 2 of the rateper cent. instead of being in hundredths order, as on the second slide,is now in the highest order of thousands period of series of columns 32,and that successive figures of the rate per cent. shows the percentage(omitting the zero) to be 55240712328 for the base ten million dollarsindicated in series of columns 33. The third slide from the top of Fi 2is to show the position of the first digits of the permanent number andthe tablet number when the slide is in its eX- treine position to theright. The object in providing supplemental slides, as those marked 1 land 2 is to enable the formation or such numbers as 333, when a slidemarked 2 and a slide marked 1 are moved to the same column to count as3. In the same manner other repeated digits may be formed by combininglower numbers on this principle.

From the preceding, it will be plain that any slide in its normalposition or to the extreme left, when drawn to the right as far aspossible will have its digi figure of the permanent number passedthrough successive orders or columns from the highest to the lowest inseries of columns 33, forming all the numbers possible to be formed bythis manipulation; and that the successive corresponding percentageswill be formed or given in the series of columns 32, owing to the factthat the tablet carrying the figures tor the necessary correspondingpercentages is successively moved through or under series of columns 32.Thus the parts of the numbers, as for ($789), last three slides of 2,are shown in series of columns 33 and the percentages for correspondingparts of said number are shown in series or columns in position foradding, the final result being obtained mainly by mechanical methods.

The bra 28, 29 and 30 serve to resist the strain oi the cords crossingthe face of the calculator as well as to mark off the spaces for theseries of columns 32 and 33 and to assist in keeping the slides andguides in place.

With either of the forms of attachment for the tablet the writingthereon is entirely unobstructed, and the tablet, which is of light cardboard or heavy paper, is held firmly in place while being easily placedin position or moved therefrom.

By means of the construction of the present invention the several slidesmay b freely moved to the positions desired without causing themovement; o1 the other slides, because of the innnovable partitionsthere- .ween, and when moved to the position c sired they are securelyheld against accidental. movement by the pressure exerted thereon by thespring actuated friction bar 1?. This friction bar 1'7, besides havingthe function of retaining the slides in their adjusted positions, alsohas the further function of regulating undue lateral friction betweenthe slides and guides arising from swelling or shrinking or warping ofthe slides and guides by changes in temperature or absorption ofmoisture. Should the slides become ditiicult to move, it is onlynecessary to adjust the nuts 20 so as to relieve the compression ofsprings 19 and tne desired degree of frictional pressure on the slidesmay be produced.

The adjustability of the stay bar 12 permits it to be moved in more orless to bear against the ends of the guides 15 and thus effectivelyprevent their longitudinal movement which might otherwise permit themovement of a slide to cause the movement of another slide.

The freedom with which the slides may be removed and replaced is also afeature of this invention, facilitating the renewal of the tablets whena change is made in the rate per cent. for which the machine is set.Either arrangement for removably securing the tablets in place assuresan efficient connection and avoids all possibility of the tal let beingtorn in passing beneath the braces or the column cords.

By means of this invention a person whose duty is to compute percentagesfor large numbers, as the town, county or city clerk in ascertaining thetax on given valuations at a fixed tax rate, may quickly and accuratelymove the slides to indicate by their permanent numbers in the series ofcolumns 33 the numbers repres nting the valuation for which the tax orother percentage is desired and then by adding together the figuresappearing in the series of columns 32 the desired result is obtained.

What I claim as my invention. is;

l. A calculating machine, comprising a frame, a series of slides thereinprovided with numbers, a spring pressed friction bar bearing on the sides and pressing them together toprevent accidental movement there of,and means on the frame by which the numbers on the slides may be read indifferent decimal orders according to the position of the slides.

2. A calculating machine, comprising a frame, a series of slides thereinprovided with numbers, a spring pressed friction bar bearing on theslides and pressing them together toprevent accidental movement thereof,and cords extending across the frame to form series of colu nns by meansof which the numbers on the slides may be read in di'tferent decimalorders according to the position of the slides.

A calculating mechine, comprising a frame, a series of slides thereinprovided with numbers, a spring pressed friction bar bearing on theslides and pressing them together toprevent accidental movement thereof,cords extending across the frame to form series of columns by means ofwhich the numbers on the slides may be read in different decimal ordersaccording to the position of the slides, and bra es extending across theframe and secured to the sides thereof to brace the frame against thetension of the cords and to marl; off spaces therebetween for the saidseries of columns.

i i-r calculating machine, comprising a frame, a series of slidestherein provided with numbers, a series of guides alternating with theslides, a spring pressed friction bar bearing on the slides and pressingthem together to prevent accidental movement thereof, and means on theframe by which the numbers on the slides may be read in differentdecimal orders according to the position of the slides.

5. fr calculating machine, comprising a frame, a series of slidestherein provided with numbers, a friction bar bearing on the series ofslides, posts mounted on the frame and entering openings of the frictionbar, springs surrounding the posts and bearing on the friction bar,adjusting nuts threaded on the posts and bearing on the springs forvarying the compression of the springs to cause the friction bar toapply pressure to the series of slides, and means on the frame by whichthe numbers on the slides may be read in different decimal ordersaccording to the position of the slides.

A. calculating machine, comprising a frame, a series of slides thereinprovided with numbers, a series of guides alternating with the slides, aspring pressed friction bar bearing on the slides and pressing themtogether to prevent accidental movement thereof, an adjustable stay barat the end of in frame bearing against the ends of the guides preventlongitudinal movement ther and means on the frame by which the numberson the slides may be read in different decimal orders according to theposition of the slides.

7. fr calculating machine, comprising a frame, a series of slidestherein provided with numbers, a series of guides alternating with theslides, a hinged end on the frame having openilgs therein, a stay barprovided vith pins riding in the openings of the hinged end of theframe, set screws mounted on the hinged end of the frame and bearing aainst the stay bar to adjust the position or the stay bar and cause itto bear against the ends of the guides to prevent their longitudinalmovement, means for holding the hinged end of the frame in its closedposition, and means on the frame by which the numbers on the slides maybe read in different decimal orders according to the position of theslides.

S. A. calculating machine, comprising a frame, a series of slidestherein provided with numbers, a series of guides alternating with theslides, a spring pressed friction bar bearing on the series of slidesand guides to hold the slides in their adjustments with pressure, anadjustable stay bar at the end of the frame bearing on the ends of theguides to prevent their longitudinal movement, and means on the frame bywhich the numbers on the slides may be read in different decimal ordersaccording to the position of the slides.

9. A calculating machine, comprising a frame, a series of slides thereinprovided with numbers, a series of guides alternating with the slides, afriction bar bearing 011 the series of slides and guides, posts mountedon the frame and entering openings of the friction bar, springssurrounding the posts and bearing on the friction bar, adjusting nutsthreaded on the posts and bearing on the springs for varying thecompression of the springs to cause the friction bar to apply pressureto the series of slides and guides, a. hinged end on the frame providedwith openings, a stay bar having pins sliding in the openings of thehinged end of the frame, set screws mounted on the hinged end of theframe and bearing on the stay bar to hold the stay bar against the endsof the guides, and means on the frame by which the numbers on the slidesmay be read in different decimal orders according to the position of theslides.

10. A calculating machine, comprising a frame, a series of alternatingslides and guides in the frame, means for applying pressure to theslides and guides, each of the slides being provided with two numbers, aseries number and a number which is the multiple of a given number bythe said serial number, means by which the serial numbers may be read indifferent decimal orders according to the positions of the slides, andmeans by which the multiple numbers may be read in corresponding decimalorders at such times.

11. A calculating machine, comprising a frame, alternating slides andguides contained in the frame, each slide having a permanent number anda temporary numb'er thereon, means by which the permanent numbers may beread in different decimal orders according to the positions of theslides, and means by which the temporary numbers may be read incorresponding decimal orders at such times.

12. in a calculating machine, a slide having its end reduced to form atablet base below the plane of the top of the slide and having a recessin the under part of its end with an inclined slot extending therefrom,a spur located in the recess, a tablet adapted to have its end fi ted inthe slot and impaled on the spur and bent around the end of the slide tolie on the tablet base, and a swinging hook mounted at the shoulder ofthe slide formed by the reduced portion thereof to engage the other endof the tablet.

In testimony whereof, I afiiX my signature, in presence of twowitnesses.

FRANK M. VVELNIAK, JOHN BOHR.

